me on this prolem ( Magnetic Field).

[vu95112]

Hell all,
I need your help. Thanks
The magnetic field 40 cm away from long, straight wire carrying current 2.00 A is 1 µ T. At one instance, the two conductors in a long household extension cord carry equal 2-A currents in opposite directions. The two wires are 3mm apart. Find the magnetic field 40 cm away from the middle of the straight cord, in the plane of the two wires.

 

[berkeman]

Hell all,
I need your help. Thanks
The magnetic field 40 cm away from long, straight wire carrying current 2.00 A is 1 µ T. At one instance, the two conductors in a long household extension cord carry equal 2-A currents in opposite directions. The two wires are 3mm apart. Find the magnetic field 40 cm away from the middle of the straight cord, in the plane of the two wires.

We do not do your homework for you. What are the relevant equations, and how will you start this problem?

 

[vu95112]

Hello,
I am sorry. I just need you help a little. Thanks
I have learn this formula
B = µ0 I / (2 п r)
Where µ0 = 4 п * 10 ^ -7, I is current , r is the radius, and п = 3.14
But, it is hard to apply on this problem

 

[berkeman]

Hello,
I am sorry. I just need you help a little. Thanks
I have learn this formula
B = µ0 I / (2 п r)
Where µ0 = 4 п * 10 ^ -7, I is current , r is the radius, and п = 3.14
But, it is hard to apply on this problem

That is the correct equation. If you plug in the numbers in the problem statement for a single wire, do you get the 1uT B-field 40cm away from the 2A current? (Be sure to convert 40cm into meters)

If so, then you just need to superpose the two magnetic fields that you get for the two wires, and be careful about your distances. Use the right hand rule to help you figure out whether the B-fields from the two wires add or subtract out at the point 40cm away from the center of the cord (in the plane of the 2 wires).

 

[vu95112]

Thank you very much. I got it.

 

[berkeman]

Sweet.